Aerosol can protected against explosion



Dec. 20, 1966 H. ABPLANALP 3,292,826

AEROSOL CAN PROTECTED AGAINST EXPLOSION 'Filed Jan. 18, 1965 INVENTOR.

&

ATTORNEY United States Patent 3,292,826 AEROSOL CAN PROTECTED AGAINST EXPLOSION Robert Henry Ahplanalp, Hewitt Ave., Bronxville, N.Y. 10460 Filed Jan. 18, 1965, Ser. No. 426,044 6 Claims. (Cl. 222-397) This invention relates generally to safety packaging of aerosols.

Aerosols are commonly contained within metal cans designed to safely contain the pressures employed to provide for dispensing of material from the can when the conventional manually operable valve associated therewith is opened. 'l' he cans will' adequately withstand these pressures under normal conditions of temperature, but if subjected to appreciable elevation in temperature may generate within the can pressures greater than the can will withstand with the result that the can may burst or explode. These situations may occur if the can is subjected for a prolonged period to direct sunlight during hot summer days or by leaving the can in the glove compartment of an automobile during hot weather. Furthermore, cases have been known where the ultimate purchaser of an aerosol will leave the same on a hot radiator in the home or place it under or immerse it in hot water in order that the viscosity of material contained therein may be lowered to produce better spraying efiiciency in cold weather.

When such explosions take place, they may result in injury to persons or property in the vicinity thereof. This is due to the fact that relatively high pressures are suddenly completely released through rupture and sometimes cause disintegration of the metal wall of the can.

The object of the present invention is to incorporate within the can a safety factor in the form of means which will act automatically, upon the building up of excess pressure, to relieve the pressure in the can in such a slow manner as to forestall bursting or explosion of the can and in a manner perfectly safe to persons and property in the vicinity thereof.

Speaking generally, the present invention consists in providing some part of the wall of the can with a weakened portion which, when subjected to excess pressure in the can, will be at least in part detached from the wall of the can in which it is formed to provide an opening forming a safety relief vent through which the pressure in the can may be relieved in such a gradual manner that no particular damage can result therefrom.

In carrying out this invention that portion of the can which constitutes the pressure relief means is preferably so located in the wall of the can that the pressure and/ or liquid in the can escapes in a downward direction laterally of the can so that a person holding or standing over the can will not be impinged by the material thus exhausted or the can caused to be propelled from the surface on which the can might be standing upright at the time.

Features of the invention, other than those adverted to, will be apparent from the hereinafter detailed description and appended claims, when read in conjunction with the accompanying drawings.

The accompanying drawings illustrate one practical embodiment of the invention, but the construction therein shown is to be understood as illustrative, only, and not as defining the limits of the invention.

FIG. 1 is a side elevation of an aerosol dispenser embodying the present invention;

FIG. 2 is a section through the dispenser showing the invention; and

FIGS. 3, 3a and 3b are enlarged sections taken in the plane of the line 33 of FIG. 1, showing different illustrative ways in which the weakening of the wall of the can to produce the safety feature thereof, may be accomplished.

In the drawing, 1 designates an aerosol dispenser can which is, in the main, of conventional form. This can is provided with a side wall 2, a bottom wall, and a top wall 3, all joined together in strong liquid-tight joints. The top wall is provided with a filling opening closed by a mounting cup 4 which has a valve stem 5 on which is mounted any appropriate valve operating dispenser cap or button 6.

The dispenser can shown is, as stated, conventional, such, for example, as shown in my Patent No. 2,631,814. The can itself is old and well known and the present invention may be associated with any dispenser can embodying the general characteristics referred to.

The present invention consists in providing the can with a safety feature embodying a weakened wall area or section such, for example, as indicated at 7 in the drawing. This weakened area is produced by partially piercing, scoring or embossing the wall of the can to provide the substantially enclosed area 7, shown in FIG. 1. This area may be of any shape and size without departing from the invention and is determined by enclosing said area by a line of weakness 8 which extends substantially about the entire area, except that there is a breach 9 in said line consisting of an unaltered section which permanently secures the area 7 to the wall of the can.

The line of weakness 8 may be produced in various ways without departing from this invention. For exam ple, the wall of the can which is generally of sheet steel, may be manipulated by the operation of scoring, punching or embossing whereby the peripheral portion 8 of the area 7 is connected to the remainder of the wall by an attenuated or thin section 8a, 8b or of FIGS. 3, 3a and 3b. In both FIGS. 3 and 3a, the attenuated sections 8a and 8b are produced by embossing or punching the wall of the container to cause a stretching of the wall into a thinner section along line 8, whereas in FIG. 3b, the wall is weakened along the line 8 by scoring the latter as shown at 8d to produce the weakened section 80. The line of weakness 8 may be produced in other ways than as stated, but in any event it embodies a wall area partially surrounded by a line of weakness 8 which is sufficiently thinner than the remainder of the wall of the container so that it will be ruptured by pressure within the can before the remaining portions of the can burst or disintegrate under excessive pressure.

Different products contained in aerosol dispensers require different pressures and the cans which contain them have conventional walls and joints well adapted to carry these pressures, the walls in some cans being thinner than in others. In any event the line of weakness 8 in the wall of a can should be such that the area 7 will be partially detached along the line of weakness before excessive pressures are generated within the can.

In practice, I preferably permanently attach the area 7 at the zone 9 which is uppermost of that area, so that, in the event that the line of weakness gives way under pressure approaching the danger point, the lower portion of the area 7 will break away first with progressive tearing away of said area in an upward direction so that, as the pressure or the pressurized material in the can is released therefrom, it will be directed down- Wardly against the surface on which the can may be resting or below the hand of the operator which in variably holds the upper portion of the can in a position to actuate the valve operating button or cap. In this way little if any danger will accompany the release of such pressure.

In the accompanying drawings, the displaceable area 7 is shown as circular in form and is positioned in and near'thebottomofthe side wall of the can. However, in practice it may form part of the top wall 3 of the can or it may form part of the base of the mounting cup 4 without departing from this invention. However, I prefer not to incorporate it in-the bottom wall of the can because the discharge of pressure against the surface on which the conventional can may be seated, might in such instance tend to forceably displace the can from that surface which would be objectionable.

Another advantage in positioning the displaceable area 7 in the side wall of the can is that, when so positioned, it may be formed in the steel from which the side wall is to be made while such steel remains inthe-flat, either before or after the application of the lithography which is commonly applied to-the exterior of aerosol cans. The forming of the safety feature in the material in-the-flat will in nowise interfere with its The foregoing detailed description sets forth the invention in its preferred practical form, but the invention is to be understood as fully commensurate with't-he appended claims.

I claim:

1. An aerosol dispenser can comprising a bottom wall, I

a side wall connected to the bottom wall, a top wall connected to the side wall, said top Wall having a filling opening, a mounting cup sealing said filling opening, a

--valve mounted-through the mounting cup, one of said Walls containing a relatively large section at 163812 1331.

wherein said section circumscribed by said line of weak-.

ness is embossed in the surface.

4. An aerosol dispenser can as described in claim-1 wherein saidline of weakness consists of a line scored in the surface.

5. An aerosol dispenser can as described in claim 1 wherein said line of weakness consists of a line partially pierced into the surface.

6. An aerosol dispenser can as described in claim 2 wherein the section partially circumscribed by the said line of weakness is located in the side wall and the unweakened portion of the area is in the direction toward 1 the top of the dispenser.

References Cited by the Examiner UNITED STATES PATENTS 985,634 2/1911 Rodgers 222-541 2,014,380 2/ 1935 Hot-hersall 222541 2,170,937 8/ 1939 Bruning. 2,301,724 11/1952 Vischer 220--44 2,951,614 9/ 1960 Greene.

3,038,627 6/1962 Daley. 3,074,602 1/ 1963 Shillady et a1. 2225-397 RAPHAEL M. LUPO, Primary Examiner. 

1. AN AEROSOL DISPENSER CAN COMPRISNG A BOTTOM WALL, A SIDE WALL CONNECTED TO THE BOTTOM WALL, A TOP WALL CONNECTED TO THE SIDE WALL, SAID TOP WALL HAVING A FILLING OPENING, A MOUNTING CUP SEALING SAID FITTING OPENING, A VALVE MOUNTED THROUGH THE MOUNTING CUP, ONE OF SAID WALLS CONTAINING A RELATIVELY LARGE SECTION AT LEAST PARTIALLY CIRCUMSCRIBED BY A SELECTED LINE OF WEAKNESS IN THE STRUCTURAL MATERIAL, SAID LINE OF WEAKNESS BEING DESIGNED TO RUPTURE AT A LOWER DISPENSER PRESSURE THAN THE RUPTURE PRESSURE OF THE REMAINDER OF THE DISPENSER. 